matita/matita/contribs/lambdadelta/basic_2/rt_transition/cpx_feqx.ma

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  14
  15 include "static_2/static/feqx.ma".
  16 include "basic_2/rt_transition/cpx_reqx.ma".
  17 include "basic_2/rt_transition/rpx_reqx.ma".
  18
  19 (* UNBOUND CONTEXT-SENSITIVE PARALLEL RT-TRANSITION FOR TERMS ***************)
  20
  21 (* Properties with sort-irrelevant equivalence for closures *****************)
  22
  23 lemma feqx_cpx_trans: ∀h,G1,G2,L1,L2,T1,T. ❪G1,L1,T1❫ ≛ ❪G2,L2,T❫ →
  24                       ∀T2. ❪G2,L2❫ ⊢ T ⬈[h] T2 →
  25                       ∃∃T0. ❪G1,L1❫ ⊢ T1 ⬈[h] T0 & ❪G1,L1,T0❫ ≛ ❪G2,L2,T2❫.
  26 #h #G1 #G2 #L1 #L2 #T1 #T #H #T2 #HT2
  27 elim (feqx_inv_gen_dx … H) -H #H #HL12 #HT1 destruct
  28 elim (reqx_cpx_trans … HL12 … HT2) #T0 #HT0 #HT02
  29 lapply (cpx_reqx_conf_dx … HT2 … HL12) -HL12 #HL12
  30 elim (teqx_cpx_trans … HT1 … HT0) -T #T #HT1 #HT0
  31 /4 width=5 by feqx_intro_dx, teqx_trans, ex2_intro/
  32 qed-.